In most cases, obesity occurs when a person consumes more calories than he burns. Inactivity, pregnancy, sleep loss, medication and heredity are a few factors that may contribute to calorie imbalances. Medical conditions, such as hypothyroidism, Cushing’s syndrome and polycystic ovarian syndrome, cause people to become obese as well.
Societal issues may also be to blame for obesity. Some individuals do not have access to safe, convenient places to exercise. They may also lack physical and financial access to grocery stores that sell healthy food options, such as fresh fruits and vegetables. Age also plays a factor. A combination of a less active lifestyle, hormonal changes and muscle loss may cause some people to gain weight.